/*
 * Copyright 2020 DuJiang.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.rc.saas.tenant.crypto.util;

import java.nio.charset.Charset;
import java.security.Security;
import java.util.UUID;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;
import org.bouncycastle.jce.provider.BouncyCastleProvider;

/**
 * AESUtils
 *
 * @author DuJiang
 */
public final class AESUtils {

    private static final String ALGORITHM = "CBC";
    private static final String AES_CBC_PKCS7Padding = "AES/CBC/PKCS7Padding";


    static {
        Security.addProvider(new BouncyCastleProvider());
    }

    /**
     * 加密
     *
     * @param encryptText 需要加密的信息
     * @param key         密钥字符串
     * @param iv          向量
     * @param charset     字符集名称
     * @return String  加密后Base64编码的字符串
     */
    public static final String encrypt(final String encryptText, final String key, final String iv, final String charset) {
        try {
            Cipher cipher = Cipher.getInstance(AES_CBC_PKCS7Padding);
            SecretKeySpec secretKeySpec = new SecretKeySpec(key.getBytes(), ALGORITHM);
            IvParameterSpec ivParameterSpec = new IvParameterSpec(iv.getBytes(charset));
            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivParameterSpec);
            return Base64.encodeBase64String(cipher.doFinal(encryptText.getBytes(Charset.forName(charset))));
        } catch (Exception e) {
            e.printStackTrace();
        }
        return encryptText;
    }

    /**
     * 解密
     *
     * @param decryptText 需要解密的信息
     * @param key         密钥字符串
     * @param iv          向量
     * @param charset     字符集名称
     * @return String 解密后的字符串
     */
    public static final String decrypt(final String decryptText, final String key, final String iv, final String charset) {
        try {
            Cipher cipher = Cipher.getInstance(AES_CBC_PKCS7Padding);
            SecretKeySpec secretKeySpec = new SecretKeySpec(key.getBytes(), ALGORITHM);
            IvParameterSpec ivParameterSpec = new IvParameterSpec(iv.getBytes(charset));
            cipher.init(Cipher.DECRYPT_MODE, secretKeySpec, ivParameterSpec);
            return new String(cipher.doFinal(Base64.decodeBase64(decryptText)), Charset.forName(charset));
        } catch (Exception e) {
            e.printStackTrace();
        }
        return decryptText;
    }

    public static void main(String[] args) {
        String aa = "197123400478960334";
		String encrypt = AESUtils.encrypt(aa, "wRTmXkLWB6p7TV3E", "yidTFfQI67evdYdq", "UTF-8");
		System.out.println(encrypt);
		System.out.println(AESUtils.decrypt("h0SdNU1fotcBrXKm/uLI6w==","wRTmXkLWB6p7TV3E", "yidTFfQI67evdYdq", "UTF-8"));
        System.out.println(UUID.randomUUID().toString());
    }

}